Nasa scientist suggest in a new study that the “graininess” of the Moon’s surface, and its accompanying shadows, could be a hiding spot for water ice.
Scientists don’t fully understand how that can be possible. Because there is no atmosphere to regulate temperature during the day, the Moon’s surface gets hot enough to boil water. If any captured water did manage to turn into ice overnight (when temperatures can get down to around -150°C or -238°F), it would all boil away once the Sun warmed it up.
Yet, somehow, studies have shown that there is water on the surface on the dayside of the Moon – seemingly sitting in incredibly hot temperatures.
“Over a decade ago, spacecraft detected the possible presence of water on the dayside surface of the Moon, and this was confirmed by NASA’s Stratospheric Observatory for Infrared Astronomy [SOFIA] in 2020,” said Jet Propulsion Laboratory (JPL) astrophysicist Björn Davidsson.
“These observations were, at first, counterintuitive: Water shouldn’t survive in that harsh environment. This challenges our understanding of the lunar surface and raises intriguing questions about how volatiles, like water ice, can survive on airless bodies.”
This isn’t really an issue if you assume that water is not free to move around on the surface – all locked up in something like rock or glass created by meteorite strikes. This is a solid theory, and we know from geological samples from past Apollo missions that this is part of the story.
However, a study in 2009 found that the amount of water changes depending on the time of day. There’s less water before noon in the hottest part of the day, but it increases again in the afternoon when it cools down a little. This suggests that at least some of the water is free to move around – getting boiled during the day and then frozen again later on.
Saurce: nasa.gov.
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